There are plenty of semi custom cabinets available that offer a standard "stacked" wall cabinet- with one long and one short section- typical 45 and 48" total height-top opening of 12"
48 brings you to 9 1/2 ft nominal, leaving 6" for molding which is nice for a stack of molding.
For instance looking at Showplace a stacked 3648 is about $215 more than a simple 3636 wall.

Many brands that don't have a standard stack will "combine" cabinets - you pick the sizes(which will be available from 12-42" high in 3" increments) and they make them as a single cabinet. Costs doing it that way vary from brand to brand--from slightly more to quite a bit.

A friend just did this with 36" and 18" stacked on top. It looks very good.

Thank you all. :)

Oops sorry 48 puts you at 8' 6" not 9'6". That's what iget for posting on my way out the door.

Okay, so with 10 feet ceilings, do you think I can stack two 30 inches-so the upper cabs will be 60 inches total-think it would work? With maybe none or a teeny bit of room for molding?

What style is your home? Personally, I prefer the look of 2/3 topped with 1/3, which is more typical of the inset panel built-ins and doors in our 1911 Craftsman. The 1/2 and 1/2 is a great look for a more modern design with slab fronts, etc. I don't think 1/2 and 1/2 would fit into a more traditional home. Go to Houzz and search on "stacked cabinets," then filter by "traditional" or "modern" and you'll see examples of both. Good luck!

Mizinformation...the house is transitional. Everything is very simple, clean lines, but there are craftsman elements. The cabinet faces will be shaker profile. Counter is luce de luna quartzite. I was going to mix a walnut stain with white for the cabs as well. I have searched houzz and can find very very few examples of what I want to do...which may tell me something. lol :) I can do 36 with 18 on top, but it would not work all the way around the kitchen as the stock cabs do not offer that for the corner or the narrow cabs on either side of sink.